1. Field of the Invention
The present invention relates to a testing method and a testing device for a monolithic ceramic capacitor including a ceramic with a high dielectric constant, and another electronic component having a negative resistance-temperature characteristic.
2. Description of the Related Art
For such electronic components, various tests are carried out before the components are shipped as final products. As one of the tests, a burn-in test is performed. In a burn-in test, a predetermined load, which is determined by a constant voltage that is higher than a rated voltage of the component being tested, is applied at a constant temperature that is higher than its rated value for a predetermined short time (burn-in time). The burn-in of an electronic component is carried out in such a manner that a load that is equal to the above-described predetermined load is applied to the electronic component. Thereafter, the insulation resistance of the inside of the component is measured. An electronic component of which the insulation resistance becomes less than a predetermined value is determined to be a rejected product and is eliminated from the group of acceptable products.
When burn-in voltage is applied to an electronic component placed in the burn-in temperature atmosphere as described above, the electronic component is self-heated due to the load current. Therefore, the temperature of the electronic component does not practically become equal to the burn-in temperature which is set in a thermostat. Moreover, the self-heating temperature is dispersed depending on electronic components.
As a burn-in test which has been carried out and by which the self-heating temperature of an electronic component can be kept constant, and the burn-in can be accurately carried out, a method in which constant power is applied is known (e.g., see Japanese Unexamined Patent Application Publication No. 6-102312, page 4, FIG. 3).
However, the above-described known burn-in testing method can be applied to electronic components for which power consumption can be correctly controlled with the use of an external control signal. However, this testing method can not be applied to electronic components for which the power consumption can not be controlled.